According to a known terminal connecting structure in a current detector mounted on a passenger vehicle, a cargo truck or the like to detect charging or discharging current of a battery, or in a fuse unit directly attached to a battery post via a battery terminal, a bolt is passed through a circular mounting hole formed through a bus bar (a metal plate), and an LA terminal (a connecting terminal) of a cable, and is tightened by a nut, whereby the cable is detachably attached to the bus bar (see Patent Document 1). As shown in FIG. 5, in a terminal connecting structure used in a current detector 501, terminal connection portions 507 of bus bars 505 which are insert molded with a device housing 503 are disposed such that the front and rear surfaces thereof are exposed. Bus bar holes 509 are opened in the terminal connection portions 507. An LA terminal 515 in which a terminal hole 513 is disposed is crimped on the end of a cable 511. The LA terminal 515 is electrically connected to the terminal connection portion 507 of the bus bar 505 in a state in which the contact pressure is provided, by inserting the shaft 519 of a bolt 517 passing through the terminal hole 513, into the bus bar hole 509, and then tightening a nut 521.
That is, in a tightening work in the terminal connecting structure using the bolt 517 and the nut 521, the LA terminal 515 is set (placed) on a terminal mounting surface of the bus bar 505, and the position of the terminal hole is aligned with the bus bar hole. Next, to prevent skew tightening from occurring, the bolt 517 is temporarily tightened. Thereafter, the bolt 517 is fully tightened. Finally, looseness of the bolt 517 is checked.